The invention relates to badges having rows of data representative holes therethrough and readers for reading the data representative holes as the badge is moved into the reader.
A badge reader of this general type has been previously proposed by R. L. Arndt and C. E. Johnson in the IBM Technical Disclosure Bulletin publication of March 1976, Vol. 18, No. 10, pages 3400-3404. This badge reader includes a PTX/LED (photo-transistor, light emitting diode) array for reading the rows of data representative holes in a holed badge moved into the reader. It also includes a carriage moved by the badge against a carriage return spring as the badge is moved into the reader and carrying a photo-transistor movable over a series of holes provided in a stationary encoder bar. There are at least as many of the encoder bar holes as rows of data representative holes in the badge being read so that an emitter signal is generated by the photo-transistor carried by the carriage for each of the rows of data representative holes in the badge. No means is provided for indicating whether the carriage is traveling in either one direction or the other.
An emitter similar to that in the publication just described in also shown in a publication by P. R. Brinson and C. E. Johnson in the IBM Technical Disclosure Bulletin entry of June 1974, Vol. 17, No. 1, pages 190 and 191. The device shown in this publication also includes a row of light sensitive devices actuated by the holes in a badge, with a flexible emitter strip traveling with a carriage actuated by the badge for providing a single emitter pulse for each of the rows of data representative holes in the badge.
Such readers and emitters are just described function quite well if the operator is certain to insert the badge into the reader in one continuous forward motion. In these cases, a single emitter pulse is generated for each of the rows of badge holes so that these holes may be read on the existence of an emitter signal. In practice, however, there is a tendency for untrained operators to insert the badge part way into the reader and then regrasp the badge for final insertion. During the regrasp time, the return spring provided for the carriage of the reader forces the badge partially out of the reader so that more than one emitter pulse is provided for at least one of the rows of data representative holes in the badge, causing an error condition to arise. The combined motions, forwardly and reversely as just described, cannot be validly read by the previous hole badge readers, since there is no mechanism to report the combined forward and reverse motions to the controls for the badge reader.